/*!
 * \file test_performance_coverage_modules.cpp
 * \brief 性能和边界条件覆盖率测试
 * 
 * \details 本文件包含WonderTrader项目中性能测试、边界条件测试、
 *          异常处理测试等，以提高代码覆盖率和系统稳定性
 * 
 * \author WonderTrader测试团队
 * \date 2024-12-15
 */

#include <gtest/gtest.h>
#include <gmock/gmock.h>
#include <memory>
#include <string>
#include <vector>
#include <thread>
#include <chrono>
#include <atomic>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <functional>
#include <queue>
#include <mutex>
#include <condition_variable>
#include <random>
#include <future>
#include <exception>
#include <unordered_map>

using namespace std;
using ::testing::_;
using ::testing::Return;
using ::testing::AtLeast;

/*!
 * \class PerformanceCoverageModulesTest
 * \brief 性能和边界条件覆盖率测试类
 * 
 * \details 测试WonderTrader项目中的性能边界、异常处理、并发安全等
 */
class PerformanceCoverageModulesTest : public ::testing::Test {
protected:
    void SetUp() override {
        test_start_time = std::chrono::high_resolution_clock::now();
    }
    
    void TearDown() override {
        auto test_end_time = std::chrono::high_resolution_clock::now();
        auto duration = std::chrono::duration_cast<std::chrono::microseconds>(
            test_end_time - test_start_time);
        
        // 性能测试应该记录详细的时间信息
        performance_log += "Test duration: " + std::to_string(duration.count()) + "us\n";
    }

protected:
    std::chrono::high_resolution_clock::time_point test_start_time;
    std::string performance_log;
};

// ========== 并发安全测试 ==========

/*!
 * \brief 测试并发数据结构的线程安全性
 * 
 * \details 模拟多线程环境下的数据操作，验证线程安全性
 */
TEST_F(PerformanceCoverageModulesTest, TestConcurrentSafety) {
    // 模拟线程安全的数据容器（使用标准mutex代替shared_mutex以兼容旧标准）
    struct ThreadSafeContainer {
        std::map<std::string, int> data;
        mutable std::mutex mutex;  // 使用标准mutex
        std::atomic<int> operation_count{0};
        
        void insert(const std::string& key, int value) {
            std::lock_guard<std::mutex> lock(mutex);
            data[key] = value;
            operation_count++;
        }
        
        bool find(const std::string& key, int& value) const {
            std::lock_guard<std::mutex> lock(mutex);
            auto it = data.find(key);
            if (it != data.end()) {
                value = it->second;
                return true;
            }
            return false;
        }
        
        void update(const std::string& key, int delta) {
            std::lock_guard<std::mutex> lock(mutex);
            auto it = data.find(key);
            if (it != data.end()) {
                it->second += delta;
                operation_count++;
            }
        }
        
        bool remove(const std::string& key) {
            std::lock_guard<std::mutex> lock(mutex);
            auto removed = data.erase(key) > 0;
            if (removed) operation_count++;
            return removed;
        }
        
        size_t size() const {
            std::lock_guard<std::mutex> lock(mutex);
            return data.size();
        }
        
        int getOperationCount() const {
            return operation_count.load();
        }
        
        std::vector<std::pair<std::string, int>> getAllItems() const {
            std::lock_guard<std::mutex> lock(mutex);
            std::vector<std::pair<std::string, int>> items;
            for (const auto& pair : data) {
                items.push_back(pair);
            }
            return items;
        }
    };
    
    ThreadSafeContainer container;
    const int thread_count = 10;
    const int operations_per_thread = 100;
    std::atomic<int> total_operations{0};
    
    // 启动多个写入线程
    std::vector<std::thread> writer_threads;
    for (int t = 0; t < thread_count / 2; ++t) {
        writer_threads.emplace_back([&container, &total_operations, t, operations_per_thread]() {
            for (int i = 0; i < operations_per_thread; ++i) {
                std::string key = "key_" + std::to_string(t) + "_" + std::to_string(i);
                container.insert(key, t * 1000 + i);
                total_operations++;
                
                // 偶尔更新一些已存在的键
                if (i % 10 == 0 && i > 0) {
                    std::string update_key = "key_" + std::to_string(t) + "_" + std::to_string(i - 5);
                    container.update(update_key, 1);
                    total_operations++;
                }
            }
        });
    }
    
    // 启动多个读取线程
    std::vector<std::thread> reader_threads;
    std::atomic<int> successful_reads{0};
    for (int t = 0; t < thread_count / 2; ++t) {
        reader_threads.emplace_back([&container, &successful_reads, t, operations_per_thread]() {
            for (int i = 0; i < operations_per_thread; ++i) {
                // 尝试读取其他线程写入的数据
                for (int other_t = 0; other_t < thread_count / 2; ++other_t) {
                    std::string key = "key_" + std::to_string(other_t) + "_" + std::to_string(i % 50);
                    int value;
                    if (container.find(key, value)) {
                        successful_reads++;
                    }
                }
                
                // 短暂休眠以增加并发竞争
                std::this_thread::sleep_for(std::chrono::microseconds(1));
            }
        });
    }
    
    // 等待所有线程完成
    for (auto& thread : writer_threads) {
        thread.join();
    }
    for (auto& thread : reader_threads) {
        thread.join();
    }
    
    // 验证并发操作结果
    EXPECT_GT(container.size(), 0);
    EXPECT_GT(successful_reads.load(), 0);
    EXPECT_GE(total_operations.load(), thread_count * operations_per_thread / 2);
    
    // 验证数据一致性
    auto all_items = container.getAllItems();
    std::set<std::string> unique_keys;
    for (const auto& item : all_items) {
        unique_keys.insert(item.first);
    }
    EXPECT_EQ(unique_keys.size(), all_items.size());  // 没有重复键
    
    performance_log += "Concurrent operations: " + std::to_string(container.getOperationCount()) + "\n";
}

// ========== 内存压力测试 ==========

/*!
 * \brief 测试内存密集型操作和内存管理
 * 
 * \details 测试大数据量处理、内存分配/释放的正确性
 */
TEST_F(PerformanceCoverageModulesTest, TestMemoryPressure) {
    // 模拟内存管理器
    struct MemoryManager {
        std::vector<std::unique_ptr<std::vector<uint8_t>>> allocated_blocks;
        std::atomic<size_t> total_allocated{0};
        std::atomic<size_t> total_freed{0};
        std::atomic<size_t> current_usage{0};
        
        std::unique_ptr<std::vector<uint8_t>> allocate(size_t size) {
            auto block = std::make_unique<std::vector<uint8_t>>(size);
            total_allocated += size;
            current_usage += size;
            return block;
        }
        
        void deallocate(std::unique_ptr<std::vector<uint8_t>> block) {
            if (block) {
                size_t size = block->size();
                total_freed += size;
                current_usage -= size;
                block.reset();
            }
        }
        
        void allocateBatch(size_t count, size_t block_size) {
            allocated_blocks.reserve(allocated_blocks.size() + count);
            for (size_t i = 0; i < count; ++i) {
                allocated_blocks.push_back(allocate(block_size));
            }
        }
        
        void deallocateBatch(size_t count) {
            size_t actual_count = std::min(count, allocated_blocks.size());
            for (size_t i = 0; i < actual_count; ++i) {
                deallocate(std::move(allocated_blocks.back()));
                allocated_blocks.pop_back();
            }
        }
        
        void clear() {
            while (!allocated_blocks.empty()) {
                deallocate(std::move(allocated_blocks.back()));
                allocated_blocks.pop_back();
            }
        }
        
        size_t getAllocatedCount() const { return allocated_blocks.size(); }
        size_t getTotalAllocated() const { return total_allocated.load(); }
        size_t getTotalFreed() const { return total_freed.load(); }
        size_t getCurrentUsage() const { return current_usage.load(); }
    };
    
    MemoryManager memory_mgr;
    
    // 测试大块内存分配
    const size_t large_block_size = 1024 * 1024;  // 1MB
    const size_t large_block_count = 10;  // 降低到10个以避免过度内存使用
    
    auto start_time = std::chrono::high_resolution_clock::now();
    memory_mgr.allocateBatch(large_block_count, large_block_size);
    auto end_time = std::chrono::high_resolution_clock::now();
    
    auto allocation_time = std::chrono::duration_cast<std::chrono::milliseconds>(
        end_time - start_time);
    
    EXPECT_EQ(memory_mgr.getAllocatedCount(), large_block_count);
    EXPECT_EQ(memory_mgr.getTotalAllocated(), large_block_count * large_block_size);
    EXPECT_EQ(memory_mgr.getCurrentUsage(), large_block_count * large_block_size);
    
    performance_log += "Large allocation time: " + std::to_string(allocation_time.count()) + "ms\n";
    
    // 测试部分释放
    start_time = std::chrono::high_resolution_clock::now();
    memory_mgr.deallocateBatch(5);
    end_time = std::chrono::high_resolution_clock::now();
    
    auto deallocation_time = std::chrono::duration_cast<std::chrono::milliseconds>(
        end_time - start_time);
    
    EXPECT_EQ(memory_mgr.getAllocatedCount(), 5);
    EXPECT_EQ(memory_mgr.getTotalFreed(), 5 * large_block_size);
    EXPECT_EQ(memory_mgr.getCurrentUsage(), 5 * large_block_size);
    
    performance_log += "Partial deallocation time: " + std::to_string(deallocation_time.count()) + "ms\n";
    
    // 清理所有内存
    memory_mgr.clear();
    EXPECT_EQ(memory_mgr.getAllocatedCount(), 0);
    EXPECT_EQ(memory_mgr.getCurrentUsage(), 0);
    EXPECT_GT(memory_mgr.getTotalAllocated(), 0);
    EXPECT_GT(memory_mgr.getTotalFreed(), 0);
}

// ========== 异常处理测试 ==========

/*!
 * \brief 测试异常处理和错误恢复机制
 * 
 * \details 模拟各种异常情况，验证系统的健壮性
 */
TEST_F(PerformanceCoverageModulesTest, TestExceptionHandling) {
    // 模拟可能抛出异常的组件
    struct ExceptionProneComponent {
        enum class ErrorType {
            NETWORK_TIMEOUT,
            INVALID_DATA,
            RESOURCE_EXHAUSTED,
            PERMISSION_DENIED,
            UNKNOWN_ERROR
        };
        
        std::map<ErrorType, int> error_counts;
        std::atomic<int> operation_attempts{0};
        std::atomic<int> successful_operations{0};
        double error_probability = 0.1;  // 10%错误率
        
        void setErrorProbability(double prob) {
            error_probability = std::max(0.0, std::min(1.0, prob));
        }
        
        void performOperation(const std::string& operation_name) {
            operation_attempts++;
            
            // 随机生成错误
            if (static_cast<double>(rand()) / RAND_MAX < error_probability) {
                ErrorType error_type = static_cast<ErrorType>(rand() % 5);
                error_counts[error_type]++;
                throwException(error_type);
            }
            
            // 模拟成功操作
            std::this_thread::sleep_for(std::chrono::microseconds(10));
            successful_operations++;
        }
        
        void performNetworkOperation() {
            operation_attempts++;
            
            // 网络操作更容易超时
            if (static_cast<double>(rand()) / RAND_MAX < error_probability * 2) {
                error_counts[ErrorType::NETWORK_TIMEOUT]++;
                throw std::runtime_error("Network timeout occurred");
            }
            
            successful_operations++;
        }
        
        void performDataValidation(const std::string& data) {
            operation_attempts++;
            
            // 数据验证失败
            if (data.empty() || data == "invalid") {
                error_counts[ErrorType::INVALID_DATA]++;
                throw std::invalid_argument("Invalid data provided");
            }
            
            successful_operations++;
        }
        
        int getErrorCount(ErrorType error_type) const {
            auto it = error_counts.find(error_type);
            return (it != error_counts.end()) ? it->second : 0;
        }
        
        double getSuccessRate() const {
            int total = operation_attempts.load();
            return (total > 0) ? static_cast<double>(successful_operations.load()) / total : 0.0;
        }
        
    private:
        void throwException(ErrorType error_type) {
            switch (error_type) {
                case ErrorType::NETWORK_TIMEOUT:
                    throw std::runtime_error("Network operation timed out");
                case ErrorType::INVALID_DATA:
                    throw std::invalid_argument("Data validation failed");
                case ErrorType::RESOURCE_EXHAUSTED:
                    throw std::runtime_error("System resources exhausted");
                case ErrorType::PERMISSION_DENIED:
                    throw std::runtime_error("Permission denied");
                case ErrorType::UNKNOWN_ERROR:
                default:
                    throw std::runtime_error("Unknown error occurred");
            }
        }
    };
    
    ExceptionProneComponent component;
    component.setErrorProbability(0.15);  // 15%错误率
    
    int successful_operations = 0;
    int caught_exceptions = 0;
    const int total_operations = 100;  // 降低操作数以加快测试
    
    // 测试一般操作的异常处理
    for (int i = 0; i < total_operations; ++i) {
        try {
            component.performOperation("test_operation_" + std::to_string(i));
            successful_operations++;
        } catch (const std::exception& e) {
            caught_exceptions++;
            // 验证异常信息不为空
            EXPECT_FALSE(std::string(e.what()).empty());
        }
    }
    
    EXPECT_GT(successful_operations, 0);
    EXPECT_EQ(successful_operations + caught_exceptions, total_operations);
    
    // 测试数据验证异常
    std::vector<std::string> test_data = {"valid_data", "", "invalid", "good_data"};
    int validation_errors = 0;
    
    for (const auto& data : test_data) {
        try {
            component.performDataValidation(data);
        } catch (const std::invalid_argument& e) {
            validation_errors++;
            EXPECT_TRUE(std::string(e.what()).find("Invalid") != std::string::npos);
        }
    }
    EXPECT_EQ(validation_errors, 2);  // ""和"invalid"应该导致异常
    
    // 验证成功率在合理范围内
    double success_rate = component.getSuccessRate();
    EXPECT_GT(success_rate, 0.5);  // 至少50%成功率
    EXPECT_LT(success_rate, 1.0);  // 小于100%（有错误）
    
    performance_log += "Exception test success rate: " + std::to_string(success_rate * 100) + "%\n";
    performance_log += "Total exceptions caught: " + std::to_string(caught_exceptions) + "\n";
}

// ========== 边界条件测试 ==========

/*!
 * \brief 测试各种边界条件和极限情况
 * 
 * \details 测试空数据、超大数据、极限值等边界条件
 */
TEST_F(PerformanceCoverageModulesTest, TestBoundaryConditions) {
    // 模拟数据处理组件
    struct DataProcessor {
        static bool validateRange(int value, int min_val, int max_val) {
            return value >= min_val && value <= max_val;
        }
        
        static std::string processString(const std::string& input) {
            if (input.empty()) {
                return "EMPTY";
            }
            if (input.length() > 10000) {
                return "TOO_LONG";
            }
            if (input.length() == 1) {
                return "SINGLE_CHAR";
            }
            return "NORMAL";
        }
        
        static std::vector<int> processVector(const std::vector<int>& input) {
            std::vector<int> result;
            
            if (input.empty()) {
                return {-1};  // 空向量标记
            }
            
            if (input.size() == 1) {
                return {input[0] * 2};  // 单元素处理
            }
            
            if (input.size() > 100000) {
                // 超大向量，只返回统计信息
                int sum = std::accumulate(input.begin(), input.end(), 0);
                return {static_cast<int>(input.size()), sum};
            }
            
            // 正常处理：每个元素加1
            result.reserve(input.size());
            for (int val : input) {
                result.push_back(val + 1);
            }
            return result;
        }
        
        static double safeDivide(double numerator, double denominator) {
            if (std::abs(denominator) < 1e-10) {
                return std::numeric_limits<double>::infinity();
            }
            return numerator / denominator;
        }
        
        static int safeMod(int dividend, int divisor) {
            if (divisor == 0) {
                return -1;  // 错误标记
            }
            return dividend % divisor;
        }
    };
    
    // 测试整数边界值
    EXPECT_TRUE(DataProcessor::validateRange(0, 0, 100));
    EXPECT_TRUE(DataProcessor::validateRange(100, 0, 100));
    EXPECT_FALSE(DataProcessor::validateRange(-1, 0, 100));
    EXPECT_FALSE(DataProcessor::validateRange(101, 0, 100));
    
    // 测试字符串边界条件
    EXPECT_EQ(DataProcessor::processString(""), "EMPTY");
    EXPECT_EQ(DataProcessor::processString("A"), "SINGLE_CHAR");
    EXPECT_EQ(DataProcessor::processString("Hello"), "NORMAL");
    
    // 测试向量边界条件
    std::vector<int> empty_vec;
    auto result = DataProcessor::processVector(empty_vec);
    EXPECT_EQ(result.size(), 1);
    EXPECT_EQ(result[0], -1);
    
    std::vector<int> single_vec = {42};
    result = DataProcessor::processVector(single_vec);
    EXPECT_EQ(result.size(), 1);
    EXPECT_EQ(result[0], 84);  // 42 * 2
    
    std::vector<int> normal_vec = {1, 2, 3, 4, 5};
    result = DataProcessor::processVector(normal_vec);
    EXPECT_EQ(result.size(), 5);
    for (size_t i = 0; i < result.size(); ++i) {
        EXPECT_EQ(result[i], normal_vec[i] + 1);
    }
    
    // 测试安全除法
    EXPECT_EQ(DataProcessor::safeDivide(10.0, 2.0), 5.0);
    EXPECT_EQ(DataProcessor::safeDivide(1.0, 0.0), std::numeric_limits<double>::infinity());
    EXPECT_EQ(DataProcessor::safeDivide(1.0, 1e-15), std::numeric_limits<double>::infinity());
    EXPECT_NEAR(DataProcessor::safeDivide(1.0, 1e-5), 100000.0, 1.0);
    
    // 测试安全取模
    EXPECT_EQ(DataProcessor::safeMod(10, 3), 1);
    EXPECT_EQ(DataProcessor::safeMod(15, 5), 0);
    EXPECT_EQ(DataProcessor::safeMod(7, 0), -1);  // 除零错误
    
    performance_log += "Boundary condition tests completed successfully\n";
}

// ========== 性能基准测试模板函数 (移到类外) ==========

template<typename Func>
void runBenchmark(const std::string& name, Func func, size_t iterations,
                  std::vector<std::pair<std::string, std::chrono::microseconds>>& results) {
    auto start = std::chrono::high_resolution_clock::now();
    
    for (size_t i = 0; i < iterations; ++i) {
        func();
    }
    
    auto end = std::chrono::high_resolution_clock::now();
    auto duration = std::chrono::duration_cast<std::chrono::microseconds>(end - start);
    
    results.emplace_back(name, duration);
}

/*!
 * \brief 测试系统性能基准和性能回归
 * 
 * \details 测试各种操作的性能指标，建立性能基准线
 */
TEST_F(PerformanceCoverageModulesTest, TestPerformanceBenchmarks) {
    std::vector<std::pair<std::string, std::chrono::microseconds>> benchmark_results;
    
    // 基准测试1：简单数学运算
    std::atomic<long long> math_result{0};
    runBenchmark("simple_math", [&math_result]() {
        math_result += (rand() % 1000) * (rand() % 1000);
    }, 10000, benchmark_results);
    
    // 基准测试2：字符串操作
    std::string test_string = "performance_test_string";
    runBenchmark("string_ops", [&test_string]() {
        std::string copy = test_string;
        copy += "_suffix";
        [[maybe_unused]] auto pos = copy.find("test");
    }, 5000, benchmark_results);
    
    // 基准测试3：向量操作
    std::vector<int> test_vector(100, 42);
    runBenchmark("vector_ops", [&test_vector]() {
        std::vector<int> copy = test_vector;
        std::sort(copy.begin(), copy.end());
        copy.push_back(rand() % 1000);
        copy.pop_back();
    }, 1000, benchmark_results);
    
    // 验证基准测试结果
    EXPECT_EQ(benchmark_results.size(), 3);
    
    for (const auto& result : benchmark_results) {
        EXPECT_GT(result.second.count(), 0);  // 所有操作都应该花费时间
        performance_log += "Benchmark " + result.first + ": " + 
                          std::to_string(result.second.count()) + "us\n";
    }
    
    performance_log += "All performance benchmarks completed successfully\n";
} 